How many algo possible???

[nishit.gupta]

finding a loop in a lisked list without modifying it.

1.reverse and check for beginning.
2.take two pointers, keep moving 1st by one and 2nd by two locations,
if they meet loop exists.
3.store addresses in an array.
is their any other possible solution???

[bytebro]

On 5 Apr, 12:29, [e-mail] wrote:

finding a loop in a lisked list without modifying it.

1.reverse and check for beginning.
2.take two pointers, keep moving 1st by one and 2nd by two locations,
if they meet loop exists.
3.store addresses in an array.

Option 2 is nearly there.

"Take two pointers. One at element 1 and the next at element 3. See
if they are equal; if not, move P1 by 1 and P2 by 2. Check and
continue. If P1 or P2 is null, there is no loop. If there is one, it
will definitely be detected. One pointer will eventually catch up
with the other (i.e. have the same value), though it might take
several traversals of the cycle to do it."

Courtesy of Peter van der Linden's excellent _Expert C Programming:
Deep C Secrets_

[Eric Sosman]

ni**********@st.com wrote:

finding a loop in a lisked list without modifying it.

1.reverse and check for beginning.
2.take two pointers, keep moving 1st by one and 2nd by two locations,
if they meet loop exists.
3.store addresses in an array.
is their any other possible solution???

Do you have a question about C?

<off-topic>

The answer to the question you asked is "Yes."

</off-topic>

--
Eric Sosman
es*****@acm-dot-org.invalid

[nishit.gupta]

On Apr 5, 5:25 am, Eric Sosman <[e-mail]:

[e-mail] wrote:

finding a loop in a lisked list without modifying it.

1.reverse and check for beginning.
2.take two pointers, keep moving 1st by one and 2nd by two locations,
if they meet loop exists.
3.store addresses in an array.

is their any other possible solution???

Do you have a question about C?

<off-topic>

The answer to the question you asked is "Yes."

</off-topic>

--
Eric Sosman
[e-mail]

Ya obviously bro...nywazz how does it matter whether c/c++
algo for detecting loop wud be same in both c n c++

[CBFalconer]

ni**********@st.com wrote:

Eric Sosman <[e-mail]:

>[e-mail] wrote:

.... snip off-topic query

>>
Do you have a question about C?

<off-topic>
The answer to the question you asked is "Yes."
</off-topic>

Ya obviously bro...nywazz how does it matter whether c/c++
algo for detecting loop wud be same in both c n c++

PLONK for boorishness, use of foolish abbreviations, c++ in a c
newsgroup, and general idiocy. I will not be annoyed further by
your existence.

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-- Francis Crick, co-discover of DNA
"There is nothing more amazing than stupidity in action."
-- Thomas Matthews

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